A transparent display device is a display device which can assume a transparent display state such that a viewer is able to see rear scenes thereof. It is usually applicable to department store display windows, perspective doors of refrigerators, front windshields of cars, vendors and other fields, and capable of producing display, interactive, and advertising and other synergistic effects. Due to its unique application scene and ability to achieve intelligent switching of scenes, the application of the transparent display device in a specific display field attracts more and more attention.
A basic structure of a conventional transparent display device comprises a transparent light guide plate of which a side surface is provided with a light source, a lower polarizer, a transparent display panel having a liquid crystal layer, and an upper polarizer stacked together in order. When the transparent display device displays an image, light emitted from the light source is guided by the light guide plate towards the lower polarizer. The light passes through the lower polarizer and then enters the transparent display panel. After passing through the deflected liquid crystal molecules in the liquid crystal layer, the light exits from the upper polarizer. However, Due to structural limitations of the conventional transparent display device, an angle of the light exiting the transparent display device is limited, and thus a viewing angle of the transparent display device is narrow.